Ladders are used for working at an elevation above ground level. Ladders include, for example, step ladders and extension ladders. Step ladders have a set of steps attached to a pair of rails. The rails are hinged to a frame to brace the ladder for free-standing use by a worker. A worker stands on one of the steps to work at an elevation, usually not many feet from the ground. An example of a step ladder is shown and described in U.S. Pat. No. 1,198,739 issued to Marciniak et al., and is incorporated herein in its entirety by reference. A double-sided step ladder is shown and described in U.S. Pat. No. 7,931,123, issued to Moldthan et al, and which is also incorporated herein in its entirety by reference.
Extension ladders are longer than step ladders, made for use leaning against another surface such as a building, and, because they have rungs and reach surfaces at higher elevations such as a roof, are best used to climb from the ground to the elevated surface from which surface the user can work. Extension ladders are not comfortable to stand on or particularly safe to work from for long periods of time.
Another type of ladder for working above ground level is called a trestle ladder, which includes two support members that are hinged at the top ends of the support members so that their opposing ends can be pivoted to a deployed position from a closed position to form a stable base. The sides of the trestle ladder have rungs. A plank is commonly placed on the rungs of two trestle ladders, thereby creating the “trestle” so as to create an elevated platform—the elevated plank—on which workers may stand.
A ladder that may be quickly positioned, is safe and reasonably comfortable for workers to stand on, and is compact for transport and storage would be of advantage.